SHOCK

Dora Baldini, her seven-year-old son Marco, and her new husband Bruno Baldini move into Dora's former home, where she lived during her first marriage to a man named Carlo. While Dora was pregnant with Marco, Carlo, an abusive heroin addict, was thought to have committed suicide at sea after his boat was found adrift. The incident resulted in Dora having a nervous breakdown and being placed in psychiatric care. With Bruno away as a commercial airline pilot, Dora is left all alone with Marco and only her shattered memory of the events of her former husband's death, caused by extensive electroshock treatment she received while institutionalized.

Marco experiences various strange occurrences in the home and is inexplicably drawn to the home's basement. Dora notices bizarre changes in Marco's personality and is disturbed to find he has shredded her underwear. Unnerved by Marco's behavior and other frightening occurrences, Dora pleads with Bruno that they move out of the house, but he ignores her. While Bruno is on a flight, Dora finds a bundle of roses with a note addressed to her from Carlo. Suspecting Marco wrote it as a twisted joke, she confronts him and slaps him in the face when he denies writing it. Dora brings Marco to her psychologist friend, Aldo Spidini, for examination. Aldo suggests that Dora's trauma from her marriage to Carlo may be triggering her to project feelings of spite or anger on Marco, though she confesses that she feels that Marco is being possessed by his deceased father.

One afternoon, Dora finds the piano playing by itself and witnesses drawings in Marco's room begin levitating but cannot find Marco. She eventually comes upon him in the den, and he asks her why she killed his father. This triggers a repressed memory, in which Dora recounts how she slit Carlo's throat with a boxcutter after he coercively injected her with heroin and LSD. Distraught over the recollection, Dora is assured by Bruno that Carlo killed himself and that her memory is only a delusion. Still, she remains steadfast that Carlo is haunting the home and possessing Marco.

Dora awakens in the middle of the night from a nightmare to banging noises emanating from the basement. She investigates the noises and finds Bruno smashing down a brick wall. Realizing Carlo's corpse has been hidden behind the wall, Bruno tells Dora that she called him for help after murdering Carlo seven years ago. Wanting to save her from prison, Bruno hid Carlo's body in the house and released his boat to sea, staging his disappearance as a possible suicide. Bruno explains that they had to return to the home so that Carlo's remains wouldn't have been discovered, which would have happened had they sold it; he then tells her once he has transferred the remains elsewhere, they can leave. In an abrupt but frenetic blind rage, Dora swings a pickaxe at Bruno, impaling him in the chest and subsequently stuffs his corpse in the open wall along with Carlo's.

Dora runs upstairs to search for Marco but finds a ghoulish apparition of Carlo lying in his bed. Then in the hallway, Marco subsequently appears and starts running towards her but suddenly transforms into Carlo as he embraces her, causing Dora to scream with terror. Dora tries to flee from the house but encounters violent poltergeist activity that prevents her from doing so. She returns to the basement, where all the furniture in the house moves toward her and she finally slashes her own throat with a boxcutter while Carlo's hand is holding the knife. Outside later, Marco sits at a table in the backyard, having tea with his father's invisible ghost. He then proceeds to push the ghost on the tree swing.

Dora recovers the truth about her husband's death and, in a frenzied state, kills Bruno, hiding his body alongside her former husband's in the wall.

The climax unmasks the roots of Dora’s trauma, blending supernatural vengeance with psychological collapse. Her final actions suggest the inescapable grip of both her guilt and the ghostly presence that has haunted her, making the film's conclusion a bleak meditation on the consequences of buried secrets and unresolved trauma.